Water-repellent textile fabrics resistant to fungi and bacteria



Patented Jan. 15, 1952 WATER-REPELLENT TEXTILE FABRICS SISTANT T FUNGIAND BACTERIA Paul V. Keyser, Jr., Moorestown, John W. Schick, Camden,and Howard D. Hartough, Pitman,

J., assignors to Socony-Vacuum Oil Com-' pany, Incorporated, acorporation of New York No Drawing. Application July 25, 1947, SerialNo. 763,743

'1 Claims. I

The present invention relates to the treatment of textiles and, moreparticularly, to the treatment of textiles to protect them againstmildew and to impart water-repellent properties or characteristics.

The textile fabricating art has always been confronted with the problemof protection of its products against mildew. With the development ofmeans to impart water-repellency to textiles, the need to make textilesresistant to the growth of mildew has increased. However, a seriousobstacle to the entirely satisfactory treatment of textiles to impartwater-repellency thereto has been the difllculty encountered inwaterproofing textiles which have been associated with substantiallywater-insoluble inorganic material.

For example, some of the most widely used agents for water-proofingtextiles are members of the group of quaternary ammonium saltsrepresented by the general formula where R is a long chain alkoxy groupor an amide of a long chain carboxylic acid and CsHsN is a pyridineradical.

It has been recognized for some time that copper salts retarded oreliminated the growth of mildew on textiles. However, it is known thatadvantage cannot be taken of the excellent waterrepellency imparted bythe quaternary ammonium salts of the general formula and the effect ofcopper salts on the spreading of mildew on textiles to combine the twoand provide a mildew-proofed, water-repellent textile fabric. In fact,most agents commercially employed to impart water-repellency to textilefabrics do not impart the property of waterre'- pellency to textileswhich have previously been impregnated with copper salts or otherforeign 2 to provide textile fabrics impregnated with a water-insolubleor only slightly water-soluble salt of a metal known to inhibit orretard the spread! ing of mildew on textile fabrics or to eliminate thegrowth of mildew on textile fabrics to a substantial extent.

The present invention likewise has as an object impartingwater-repellency to fibrous material associated with substantiallywater-insoluble inorganic material.

Other objects and advantages will become apparent from the followingdescription.

In the copending application Serial No. 763,744 filed July 25, 1947, inthe names of John W. Schick, Howard D. Hartough and Darwin E.Badertscher,

now Patent No. 2,559,260, a method of treating fibrous textile materialto impart the property of water-repellency is disclosed. Briefly, theaforesaid method comprises impregnating the aforesaid fibrous materialwith an aqueous solution of a water-soluble derivative of nitrogenousresinous material containing at least one 5-membered heterocyclicradical per polymer unit and preferably at least one thiophene radicalper polymer unit. After the fibrous material is impregnated with thewater-soluble derivative, the impregnated fibrous material is treated toconvert the water-soluble derivative to the insoluble mother material,the fibrous material washed substantially free from foreigncontaminating non-nitrogenous material, the so-treated fibrous materialsubjected to contact with formaldehyde, washed and heat-treated at lowtemperatures.

It now has been discovered that contrary to prior experience with otheragents capable of imparting water-repellency to fibrous textile materialthat such fibrous material can be mildewproofed and then madewater-repellent by impregnation with the aforesaid nitrogenous resinousmaterial.

In general, the novel process comprises impregnating the fibrous organicmaterial with a water-soluble salt of a metal such as copper, zinc,mercury, etc., converting the aforesaid watersoluble salt in situ to awater-insoluble salt and then impregnating the salt impregnated fibrousorganic material with the aforesaid nitrogenous resinous material in themanner set forth in the aforesaid copending application.

The following examples are illustrative but not limiting of the novelprocess.

EXAMPLE I A sample of cotton poplin 7' inches square was contacted withan aqueous solution of copper acetate. (Other water-soluble salts ofcopper, meraaazlavo cury, zinc and the like with acids of about the sameor lower dissociation constant may be used.) The concentration ofwater-soluble copper salt may be varied within wide limits but apractical concentration is about 5 to about weight per cent. The textileimpregnated with the watersoluble metal salt is then treated in anysuitable manner with a compound which through metathesis produces awater-insoluble metal salt in situ and a water-soluble derivativeof theanion of the water-soluble metal salt. For practical purposes a textileimpregnated with a copper salt is treated preferably with an aqueoussolution of trisodium phosphate. The concentration of trisodiumphosphate may vary within wide limits but a concentration of 5 to weightper cent is preferred for practical operation. The reaction may berepresented by the following equation:

where Act=CHsCOO.

The textile impregnated with the substantially water-insoluble metalsalt is then dried and contacted, for example, by immersion in anaqueous bath, with the nitrogenous, resinous material containing atleast one 5-membered heterocyclic radical per polymer unit. Forindustrial purposes at this time it is preferred to use a water-solublederivative of nitrogenous resinous material containing at least onethiophene nucleus per polymer unit in the form of an aqueous bathcontaining about 6 weight per cent of the nitrogenous thiophene resin.The textile now impregnated with a substantially water-insoluble metalsalt and a water-soluble derivative of the nitrogenous resinous materialis treated to convert the water-soluble resinous material to aWater-insoluble form. A satisfactory method for achieving this endcomprises immersing the impregnated cloth in an aqueous solution ofsodium acetate. A concentration of 10 weight per cent sodium acetate hasgiven satisfactory results. Thereafter, the textile impregnated withsubstantially waterinsoluble metal salt and substantially waterinsolublenitrogenous resinous material is washed in cold water to remove looselyattached surface precipitate. The washed or rinsed textile is thencontacted with formaldehyde. At the present time for practical reasonsit is preferred to use an aqueous alkaline bath containing formaldehydeand an alkali. Suitable concentrations are about12 weight per centformaldehyde and about 1 weight per cent sodium hydroxide. Of course,

lesser and greater concentrations may be used and'other alkalies such aspotassium hydroxide, alkali metal carbonates and, briefly, aqueousalkaline formaldehyde solutions of about the same pH as an aqueous 1weight per cent NaOH- 12..

A sample of cotton poplin 7 inches square was subjected to a cyclecomprising immersion in aqueous copper acetate and then immersion inaqueous trisodium phosphate three times. Thereafter, the so-treatedpoplin was impregnated with a nitrogenousthiophene P lymer in the mannerdescribed hereinbefore. After two hand-washings the treated textile gavea spray-rating of 70.

Both of the samples produced as described hereinbefore were subjected tosevere laundering in a washing machine to determine the effect upon thespra rating. The results are tabulated in the following table:

. Table [launder-ability vs. spray rating of cotton impregnated withCuAPOd, and thiophene water-repellent.

Spray Rating I Time (min.) in W ashing Machine 140 One treat of Threetreats 5% Cu++ 0:59;, Cu++ After the final washing, a sample of thecloth was weighed and burned to an ash in a crucible. After an hour'sburning over a Meeker burner the crucible was cooled and weighed. Anash, amounting to 5.1 per, cent by weight, was obtained. The originalcloth is said to have an ash of less than 0.1 per cent.

Satisfactory material for imparting waterrepellency to mildew-proofedorganic fibrous material can be prepared in accordance with thedisclosure provided in the copending application for United StatesLetters Patent Serial No. 636,- 511 filed December 21, 1945, nowabandoned, in the names of Howard D. Hartough and Sigmund J.Lukasiewicz. However, a material, preferred at this time for impartingwater-repellency to mildew-proofed organic fibrous material, can beprepared by reacting thiophene or a derivative thereof as defined in theaforesaid copending application with formaldehyde or its polymers andammonium halide in the presence of an acid having an ionization constantgreater than 1 10- such as [HSOal-, (S02), (NaHSOs), acetic acid,arsenic acid, benzoic acid, haloalkanoic acid, citric acid, formic acid,fumaric acid, moleic acid, etc. (Table pages 1396-7, Langes Handbook ofChemistry, 5th Ed.) The $02, for example, may be added as the compoundsulfur dioxide or may be present in the reaction mixture in the form ofa soluble compound ionizing to give the radical [H803]: such as metalbisulfites. This method is described more fully in the copendingapplication for United States Letters Patent Serial No. 781,754 filed inthe names of John W. Schick and Howard D. Hartou h On October 23, 1947.

Illustrative of the method of preparing material preferred at this timefor imparting waterrepellency to mildewproofed organic fibrous materialis the following illustrative example taken from the aforementionedcopending application' for United States Letters Patent Serial170.781.754.

A mixture of about 84 parts by weight of thiophene (about one mole),about parts by weight of 37 per cent aqueous formaldehyde (about 1.2moles), about 27 parts by weight of ammonium chloride (about 0.5 mole)and about 52 parts by weight of sodium bisulfite (about 0.5 mole), i. e.1.0 mole equivalent ofHSOr or 0.5 mole sulfurous acid, was refluxed forabout 5 hours. Upon cooling to ambient temperature a crystallinevprecipitate formed which, when separated and recrystallized from hotwater, gave a white crystalline product of the following analysis:sulfur, 18.6 per cent; nitrogen,-4.87 per cent In the description givenhereinbefore of the present invention and in the claims hereinafter, theterm fibrous material includes wool, cotton, linen, silk, rayon, nylon.hemp, jute and various artificial fibers of organic material in the formof threads, skeins or in woven form as well as paper, sheeted cellulose,leather, fur and the like. Thus, for example, fishing nets as such orthe twine from which the nets are made "may be treated as describedhereinbefore to provide a net which will'not absorb as much water asuntreated nets and at the same time the nets will be resistant to attackby fungi and/or bacteria. Furthermore, the term "5-membered heterocycliccompounds" includes furan, pyrrole, thiophene and derivatives thereofhaving stable electropositive nuclear substituents other than unstable(OH)- and (NHz)- groups. In addi tion, the treatment with metal salts tomildewproof the fabric before imparting water-repellency can be modifiedto fire-retard the fibrous material before imparting water-repellency.That is to say, instead of or in addition to mildew-proofing the fibrousmaterial, the fibrous material may be impregnated with any of the wellknown inorganic materials known to the art to impart resistance to fireand then treated to make the fibrous material water-repellent. Thus, thepresent invention includes such treatment as provides fibrous materialassociated with an inorganic salt and a nitrogenous resinous materialhaving at least one 5-membered heterocyclic radical per polymer unit andparticularly with nitrogenous resinous material having at least oneS-membered heterocyclic radical having sulfur or oxygen as theheterocyclic atom per polymer unit.

We claim:

I. The method for producing mildew-proofed, water-repellent organicfibrous material, which comprises contacting organic fibrous materialwith a first aqueous solution containing about 5 to about weight percent of copper acetate to sorb at least a portion of said copper salt onsaid fibrous material, separating said fibrous material and sorbedcopper salt from said first aqueous solution, contacting the so-treatedfibrous material with a second aqueous solution containing about 5 toabout weight per cent of trisodium phosphate, thereby obtaining treatedfibrous material having sorbed water insoluble copper salt, separatingthe so-treated fibrous material from said second aqueous solution,contacting the so-treated fibrous material with, a

third aqueous solution containing a water-soluble nitrogenous material,said nitrogenous material being obtained by reacting a heterocycliccompound selected from the group consisting of furan, pyrrole andthiophene with at least a molecular equivalent per mole of saidheterocyclic compound of a nitrogenous compound selected from one groupconsisting of hydroxyl substituted ammonium halide and ammonium halidehavin a molecular weight calculated as NHiX, where X is halogen, greaterthan 38 and with formaldehyde to obtain water-soluble nitrogenousmaterial, thereby obtaining organic fibrous material with sorbedwater-insoluble copper salt and sorbed water-soluble nitrogenousmaterial, separating the so-treated fibrous material from said thirdaqueous solution, contacting the sotreated fibrous material with afourth aqueous sodium acetateto convert said sorbed watersolublenitrogenous material into sorbed waterlnsoluble nitrogenous material,separating the so-treated fibrous material from said fourth aqueoussolution, water-washing the so-treated fibrous material, contacting theso-treated fibrous material with a fifth aqueous, alkaline solutioncontaining formaldehyde, having a pH of about that of an aqueoussolution containing 1% NaOH and 12% formaldehyde, separating theso-treated fibrous material from said fifth aqueous solution,heat-treating the so-treated fibrous material at about to about C.. andwater-washing the so-trea'ted fibrous material whereby mildewproofed,water-repellent organic fibrous material is obtained.

2. The method for producing mildew-proofed, water-repellent organicfibrous material which comprises contacting organic fibrous materialhaving sorbed water-insoluble inorganic copper compound selected fromthe group consisting of furan, pyrrole and thiophene with more than 0.25mole per mole of heterocyclic compound of a nitrogenous compoundselected from the group consisting of hydroxyl substituted ammoniumhalide andammonium halide having a molecular weight calculated as NH4X,where X is halogen,

greater than 38 and with formaldehyde, to obtain water-solublenitrogenous material, thereby obtaining organic fibrous material havingsorbed water-insoluble copper salt and sorbed water- .solublenitrogenous material, separating the sotreated fibrous material fromsaid first aqueous solution, contacting the so-treated fibrous materialwith a second aqueous solution containing sodium acetate to convert saidsorbed watersoluble nitrogenous material into sorbed waterinsolublenitrogenous material, separating the so-treated fibrous material fromsaid second aqueous solution, water-washing the so-treated fibrousmaterial, contacting the water-washed fibrous material with a thirdaqueous alkaline solution containing formaldehyde having a pH of aboutthat of an aqueous solution containing 1% NaOH and 12% formaldehyde,separating the so-treated fibrous material from said third aqueoussolution, heat treating the so-treated fibrous material at about 115 toabout 120 C., and water-washing the so-treated fibrous material wherebymildew-proofed, water-repellent organic fibrous material is obtained.

3. The method for producing mildew-proofed, water-repellent organicfibrous material which comprises contacting organic fibrous materialhaving sorbed'water-insoluble salt of a metal selected from the groupconsisting of copper, zinc and mercury, with a first aqueous solutioncontaining water-soluble nitrogenous material to obtain/organic fibrousmaterial having sorbed water-insoluble inorganic salt and sorbedwatersoluble nitrogenous material, said nitrogenous material beingobtained by reacting a heterocyclic compound selected from the groupconsisting of furan, pyrrole and thiophene with more than 0.25 mole permole of heterocyclic compound of a nitrogenous compound selected fromthe group consisting of hydroxyl substituted ammonium chloride andammonium chloride and with formaldehyde to obtain water-solublenitrogenous material. contacting the so-treated fibrous material with anaqueous solution of a salt aacaoro water-repellent organic fibrousmaterial which comprises contacting mildew-proofed organic fibrousmaterial having sorbed water-insoluble salt of a metal selected from thegroup consisting of copper, zinc and mercury with a first aqueoussolution containing a hydrohalide of a nitrogenous condensation productof thiophene to obtain organic fibrous material having said sorbedwater-insoluble salt of said metal and sorbed hydrohalide, saidhydrohalide of a nitrogenous condensation product of thiophene havingbeen obtained by reacting thiophene, formaldehyde and more than 0.25mole per mole of thiophene of an ammonium halide having a molecularweight greater than 38, contacting the so-treated fibrous material witha solution of sodium acetate to convert said sorbed water-solublehydrohalide to sorbed water-insoluble nitrogenous condensation product,contacting the so-treated fibrous material with an aqueous solution offormaldehyde having about the pH of an aqueous solution containing 1%NaOH and 12% formaldehyde, heattreating at a temperature of about 115 toabout 120 C. the so-treated fibrous material, and laundering theso-treated fibrous material whereby mildew-proofed, water-repellentorganic fibrous material is obtained.

5. The method for producing mildew-mooted, water-repellent organicfibrous material which comprises contacting mildew-proofed organicfibrous material having sorbed copper phosphate with an aqueous solutioncontaining a hydrochloride of a nitrogenous condensation product ofthiophene to obtain mildew-proofed organic fibrous material havingsorbed copper phosphate and sorbed hydrochloride of said nitrogenouscondensation product of thiophene, said hydrochloride having beenobtained by reacting thiophene, formaldehyde and more than 0.25 mole ofammonium chloride per mole of thiophene, contacting the so-treatedorganic fibrous material with an aqueous solution of sodium acetate toconvert said sorbed water-soluble hydrochloride to a sorbedwater-insoluble nitrogenous condensation product o1' thiophene.contacting thosetreated organic fibrous material with an aqueoussolution containing about 1% NaOH and about 12% formaldehyde,heat-treating the so-treated organic fibrous material at about to aboutC. and laundering the so-treated organic fibrous material, wherebymildew-proofed, waterrepellent organic fibrous material is obtained.

. 6. Organic fibrous material having sorbed water-insoluble inorganicmaterial selected from the group consisting of water-insoluble salts ofcopper. zinc and mercury inhibiting the growth of mildew and havingsorbed nitrogenous resinous material suflicient to increase thewater-repellency of said fibrous material, said nitrogenous resinousmaterial having as its principal component the reaction product offormaldehyde, 9. material selected from the group consisting of furan,pyrrole and thiophene and at least 0.25 mole per mole of saidheterocyclic compound of a material selected from the group consistingof hydroxyl substituted ammonium halide and ammonium halide having amolecular weight calculated at NHrX, where X is halogen, greater than38.

7. Organic fibrous material having sorbed water-insoluble inorganicmaterial selected from the group consisting of water-insoluble salts ofcopper. zinc and mercury and having sorbed nitrogenous, resinousmaterial suflicient to increase the water-repellency of said fibrousmaterial, said nitrogenous material having as its principal component,the reaction product of formaldehyde, thiophene and more than 0.25 moleof ammonium chloride per mole of thiophene.

PAUL V. KEYSER, JR. JOHN W. SCHICK. HOWARD D. HARTOUGH.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PA'I'ENTS Number Name Date 2,043,137 White June 2, 19362,098,942 Brubaker Nov. 16, 1937 2,147,057 Platt et al Feb. 14, 19392,169,576 Booth et a1 Aug. 15, 1939 2,306,924 Zerweck et a1 Dec. 29,1942 2,345,966 Fiedler et a1 Apr. 4, 1944 2,369,948 D'Alelio Feb. 20,1945 2,381,863 Benignus Aug. 14, 1945 ,453,085 Caeser Nov. 2, 19482,453,086 Caeser Nov. 2, 1948

1. THE METHOD FOR PRODUCING MILDEW-PROOFED, WATER-REPELLENT ORGANICFIBROUS MATERIAL, WHICH COMPRISES CONTACTING ORGANIC FIBROUS MATERIALWITH A FIRST AQUEOUS SOLUTION CONTAINING ABOUT 5 TO ABOUT 10 WEIGHT PERCENT OF COPPER ACETATE TO SORB AT LEAST A PORTION OF SAID COPPER SALT ONSAID FIBROUS MATERIAL, SEPARATING SAID FIBROUS MATERIAL AND SORBEDCOPPER SALT FROM SAID FIRST AQUEOUS SOLUTION, CONTACTING THE SO-TREATEDFIBROUS MATERIAL WITH A SECOND AQUEOUS SOLUTION CONTAINING ABOUT 5 TOABOUT 15 WEIGHT PER CENT OF TRISODIUM PHOSPHATE, THEREBY OBTAININGTREATED FIBROUS MATERIAL HAVING SORBED WATER INSOLUBLE COPPER SALT,SEPARATING THE SO-TREATED FIBROUS MATERIAL FROM SAID SECOND AQUEOUSSOLUTION, CONTACTING THE SO-TREATED FIBROUS MATERIAL WITH A THIRDAQUEOUS SOLUTION CONTAINING A WATER-SOLUBLE NITROGENOUS MATERIAL, SAIDNITROGENOUS MATERIAL BEING OBTAINED BY REACTING A HETEROCYCLIC COMPOUNDSELECTED FROM THE GROUP CONSISTING OF FURAN, PYRROLE AND THIOPHENE WITHAT LEAST A MOLECULAR EQUIVALENT PER MOLE OF SAID HETEROCYCLIC COMPOUNDOF A NITROGENOUS COMPOUND SELECTED FROM ONE GROUP CONSISTING OF HYDROZYLSUBSTITUTED AMMONIUM HALIDE AND AMMONIUM HALIDE HAVING A MOLECULARWEIGHT CALCULATED AS NH4X WHERE X IS HALOGEN, GREATER THAN 28 AND WITHFORMALDEHYDE TO OBTAIN WATER-SOLUBLE NITROGENOUS MATERIAL, THEREBYOBTAINING ORGANIC FIBROUS MATERIAL WITH SORBED WATER-INSOLUBLE COPPERSALT AND SORBED WATER-SOLUBLE NITROGENOUS MATERIAL SEPARATING THESO-TREATED FIBROUS MATERIAL FROM SAID THIRD AQUEOUS SOLUTION, CONTACTINGTHE SOTREATED FIBROUS MATERIAL WITH A FOURTH AQUEOUS SOLUTION CONTAININGABOUT 10 WEIGHT PER CENT SODIUM ACETATE TO CONVERT SAID SORBEDWATERSOLUBLE NITROGENOUS MATERIAL INTO SORBED WATERINSOLUBLE NITROGENOUSMATERIAL, SEPARATING THE TREATED FIBROUS MATERIAL FROM SAID FOURTHAQUEOUS SOLUTION, WATER-WASHING THE SO-TREATED FIBROUS MATERIAL,CONTACTING THE SO-TREATED FIBROUS MATERIAL WITH A FIFTH AQUEOUS,ALKALINE SOLUTION CONTAINING FORM ALDEHYDE, HAVING A PH OF ABOUT THAT OFAN AQUEOUS SOLUTION CONTAINING 1% NAOH AND 12% FORMALDEHYDE, SEPARATINGTHE SO-TREATED FIBROUS MATERIAL FROM THE SAID FIFTH AQUEOUS SOLUTION,HEAT-TREATING THE SO-TREATED FIBROUS MATERIAL AT ABOUT 115* TO ABOUT120* C., AND WATER-WASHING THE SO-TREATED FIBROUS MATERIAL WHEREBYMILDEWPROOFED, WATER-REPELLENT ORGANIC FIBROUS MATERIAL IS OBTAINED.